Topical composition of unsaturated monoacid/monoacrylamide/polyfunctional monomer copolymer

ABSTRACT

A thickener comprises a water-in-oil reverse emulsion and a copolymer having moieties derived (i) from a monounsaturated monocarboxylic acid monomer containing from 3 to 5 carbon atoms, the monocarboxylic acid either being in free form or in the form of an inorganic salt, and (ii) from a monoacrylamide monomer. The copolymer is in solution in the aqueous phase constituting the emulsion, the oil phase of this emulsion consisting of a mixture of at least one volatile oil and at least one non-volatile oil. The weight ratio between the volatile oil and the non-volatile oil is between 90/10 and 10/90. The oil phase represents from 10 to 60% by weight of the whole. Water represents from 30 to 70% by weight of the whole. The copolymer represents from 10 to 30% by weight of the whole and a surfactant represents from 5 to 20% by weight of the whole.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of copending application Ser. No.08/904,931, filed Aug. 1, 1997, U.S. Pat. No. 6,136,305, which is a filewrapper continuation of Serial No. 08/596,186, filed Feb. 15, 1996,abandoned, which was the 35 USC 371 national phase of Internationalapplication PCT/FR95/00833 filed on Jun. 22, 1995, which designated theUnited States.

The present invention relates, on the one hand, to a topicalcomposition, which is useful in particular in cosmetics and indermopharmacy, comprising an aqueous phase and a thickener, and, on theother hand, to a novel thickener in its normal state, which is welltolerated by the skin and mucosae.

Patent application EP-A-0,424,260 and international application WO92/21316 describe cosmetic compositions or compositions for treatingkeratinous material which may comprise an ammonium acrylate/acrylamidecopolymer dispersed in a water-in-oil emulsion. This dispersioncomprises oleosoluble surfactants having a hydrophilic/lipophilicbalance (or HLB) of less than 7. It is useful as a thickener. TheApplicant has, however, been able to observe that this type ofthickener, in the form of a dispersion, is poorly suited to thepreparation of certain compositions, such as emulsions comprising atleast one oil phase and at least one aqueous phase. The reason for thisis that this type of thickener is difficult to mix with the polar oilsliable to constitute the oil phase of these emulsions.

Patent application EP-A-0,503,853 describes topical compositions, thatis to say compositions intended to be applied to human or animal skin ormucosae, comprising a thickener consisting of a water-in-oil reverseemulsion and a copolymer. The copolymer is essentially in solution inthe aqueous phase constituting the said reverse emulsion. The copolymerconsists of units derived (a) from a monoacrylamide monomer, (b) from a2-acrylamido-2-methylpropanesulphonic (AMPS) acid monomer and (c) from apolyfunctional monomer. Such a thickener has the advantage of being ableto invert itself when it is diluted in a hydrophilic phase. Thus, whenthe thickener which comprises a water-in-oil reverse emulsion is mixedwith the other components forming the said topical composition, thesense of the emulsion is reversed, such that the aqueous phase becomescontinuous. This thickener is entirely suitable for the preparation oftopical compositions comprising, in particular, polar oils with which itis fully miscible. The thickener also has the advantage of beingrelatively well tolerated by the skin tissues and mucosae on which it isapplied.

However, the Applicant has been able to observe that the thickeners usedin the topical compositions according to patent applicationEP-A-0,503,853 could not conveniently be used for the manufacture of alltypes of topical compositions. Thus, it may be difficult to preparefluid emulsions, thickened by thickeners of this type, in a reproduciblemanner in terms of viscosity. “Fluid emulsions” is understood here torefer to topical compositions having a viscosity of less than about 25Pa s (Brookfield, LV4, 6 revolutions/minute). The reason for this isthat topical compositions of this type require relatively low contentsof the said thickener. Now, on account of the nature of the latter,slight variations in the thickener concentrations used may lead toconsiderable variations in the viscosity of the topical composition. Itis thus difficult to prepare topical compositions with such a thickenerin a reproducible manner on an industrial scale.

It has also been observed that the viscosity-modifying effect affordedby the thickener described in the above document is reduced when thisthickener is combined in the topical composition with electrolytes, suchas sodium chloride or magnesium chloride.

Moreover, patent application EP-A-0,186,361 describes thickeners whichare useful for preparing pasty printing inks. The thickener consists inparticular of a water-in-oil emulsion comprising an aqueous phase inwhich is dissolved a homopolymer or copolymer based, preferably, onmoieties derived from acrylic acid. Like the thickener described inEP-A-0,503,853, this thickener is prepared according to the process,which is known per se, of reverse emulsion polymerization. According tothis process, the polymerization of monomers is performed in awater-in-oil emulsion. The oil phase constituting this emulsion isusually based on a volatile oil, such as an isoparaffin oil. However,the Applicant has observed that-this thickener was not well tolerated bythe skin.

The Applicant has thus developed a topical composition which constitutesa first subject of the invention, circumventing the abovementioneddrawbacks of topical compositions. More particularly, the topicalcomposition according to the invention comprises a thickener based on areverse emulsion, which is well tolerated by the tissues on which it isapplied, and which moreover has a viscosity which is stable even in thepresence of electrolytes.

According to another aspect, the invention relates to topicalcompositions, in particular fluid emulsions, comprising a thickener, itbeing possible for the said topical composition to be readily preparedin a reproducible manner on an industrial scale.

According to yet another aspect, the invention relates to a thickenercomprising a copolymer, which may readily be used for thickening andemulsifying a topical composition comprising a reverse emulsion, thesaid thickener making it possible to obtain very good tolerance withrespect to the tissues on which it is applied.

The present invention thus relates to a topical composition comprisingat least one aqueous phase, a non-volatile oil and a thickener,characterized in that the thickener is chosen from those comprising awater-in-oil reverse emulsion and a copolymer having moieties derived(i) from a monounsaturated monocarboxylic acid monomer containing fromthree to five carbon atoms, the monocarboxylic acid either being in freeform or in the form of an inorganic salt, and (ii) from a monoacrylamidemonomer, the copolymer being in solution in the aqueous phaseconstituting the reverse emulsion and the oil phase of the reverseemulsion comprising at least one volatile oil.

Within the context of the present invention, it is clearly understoodthat the sense of the emulsion constituting the thickener is the senseexisting prior to the mixing of this thickener with the other componentsconstituting the topical composition, in particular the hydrophiliccomponents. Thus, it is notable that the thickener, in accordance withthe invention, comprising a water-in-oil reverse emulsion, may invert toform an emulsion in which the continuous phase is an aqueous phase, thisinversion taking place during dilution of the thickener with ahydrophilic phase constituting the topical composition.

After inversion, the copolymer is released into the continuous phase andthereby imparts increased viscosity thereto.

Other aspects of the present invention will emerge from the descriptionwhich follows and from the FIGURE.

The FIGURE represents the viscosity, measured by a Brookfield LV4viscometer rotating at 6 revolutions/minute, of a topical compositionobtained using increasing concentrations of a thickener in accordancewith the invention, compared with the viscosity of a similar topicalcomposition of the prior art, also comprising a thickener.

The Applicant has observed that a topical composition comprising anon-volatile oil as well as a thickener as described above was perfectlytolerated by the tissues on which it was applied.

The non-volatile oil present in the topical composition may be aconstituent, at least in part, of the oil phase of the reverse emulsionforming the thickener. This oil phase thus consists essentially of amixture of at least one volatile oil and at least one non-volatile oil.In this case, the weight ratio between the volatile oil and thenon-volatile oil in the water-in-oil reverse emulsion forming thethickener is usually between 90/10 and 10/90, preferably between 30/70and 70/30.

The weight ratio between the non-volatile oil and the volatile oil inthe topical composition in accordance with the invention is usuallygreater than 0.5:1, preferably greater than 0.9:1 and more generallybetween 1.1 and 100:1.

Within the context of the present invention, in order to determinewhether or not an oil is volatile, the following test is performed: 3 gof the oil to be considered are introduced into a 250 ml container whichis maintained at 220° C. for 1 h 30. The weight loss is then measured.An oil is considered as being volatile if, under these conditions, thepercentage weight loss is greater than 5%.

As volatile oils which are suitable within the context of the invention,mention may be made of volatile isoparaffins and volatile silicone oils,in particular volatile cyclomethicones. The volatile isoparaffins whichmay be used in the context of the present invention have a saturatedbranched hydrocarbon structure and a molecular weight of less than about200. Isoparaffin oils which may more particularly be mentioned areISOPAR M and ISOPAR L marketed by the company Exxon.

Non-volatile oils which may be mentioned are thickened or light liquidparaffins as defined in the European Pharmacopoeia, triglycerides ofplant origin (plant oil), esters formed by condensation between a fattyacid and a monoalcohol, the said ester containing more than 10 carbonatoms, preferably from 14 to 34 carbon atoms, such as cetearyl octanoateor isostearyl isostearate, and non-volatile silicone oils such asnon-volatile dimethicones.

According to an advantageous aspect of the invention, the volatile oilis an isoparaffin oil and the non-volatile oil comprises at least oneliquid paraffin or isostearyl isostearate.

The monounsaturated monocarboxylic acid constituting the said copolymermay be chosen from the group consisting of acrylic acid, methacrylicacid, methylmethacrylic acid or mixtures of these acids, these acidsbeing in free form or -in the form of an inorganic salt. When theseacids are in the form of a salt, this is advantageously a salt of analkali metal, preferably sodium, or even an ammonium salt. Acrylic acidin free form or in sodium salt form is preferred within the context ofthe present invention.

The molar ratio between the monocarboxylic acid and the acrylamideconstituting the said copolymer may be between 85/15 and 15/85,preferably between 60/40 and 40/60.

The copolymer also usually contains a polyfunctional monomer. Thismonomer may consist of methylenebis(acrylamide) (MBA), diallylphthalate, glycol diacrylates, triallyl cyanurate, triallylisocyanurate, polyfunctional alkylene-ethers, allyl methacrylate ormixtures of one or more of these polyfunctional monomers. Apolyfunctional monomer preferred within the context of the presentinvention consists of MBA.

The content of polyfunctional monomers present in the copolymer may bebetween 0.1 and 2 milliequivalents/mol of the other monomers.

The thickener may also advantageously contain one or more surfactants.These surfactants are preferably of the nonionic type, such aspolyethoxylated fatty alcohols, polyethoxylated alkylphenols such aspolyethoxylated nonylphenol, polyethoxylated sorbitan esters, sorbitanesters, alkylolamides or alkyl polyglycosides, in particular thosedefined in patent applications EP-A-0,077,167 or EP-A-0,358,216,reference to which is incorporated in the present description.

According to a most particularly advantageous aspect of the presentinvention, the thickener used comprises one or more surfactants whoseHLB is greater than or equal to 8, preferably greater than or equal to10.

A thickener according to the invention may be prepared according to theprocess described in patent application EP-A-0,186,361, reference towhich is incorporated in the present description, in particular thepassages on page 7, lines 1-9 and page 10, lines 22-37, as well asExamples 1, 3 and 5.

According to that process, the various monomers constituting thecopolymer are placed in aqueous solution. This aqueous solution is thenmixed with an oil phase comprising one or more surfactants, inparticular nonionic surfactants. These surfactants have an HLB value ofless than 9. The aqueous solution and the oil phase thus form awater-in-oil emulsion, after which the monomers of the aqueous phase arecopolymerized using, in a conventional manner, polyfunctional monomerssuch as those mentioned above. The oil constituting the oil phase of thesaid water-in-oil reverse emulsion usually consists of one or morevolatile oils.

When the thickener in accordance with the invention contains anon-volatile oil, this oil may be incorporated into the oil phase of thewater-in-oil emulsion after copolymerization. Nonionic surfactants suchas those mentioned above may also be added after copolymerization, forthe purpose of obtaining an HLB greater than or equal to 8 preferablygreater than or equal to 10.

According to an advantageous aspect of the present invention, thethickener used comprises a water-in-oil emulsion containing from 10 to60% by weight of oil phase, from 30 to 70% by weight of water, from 10to 30% by weight of a copolymer and from 5 to 20% by weight ofsurfactant.

A topical composition according to the invention, intended to be appliedto human or animal skin or mucosae, may consist of a topical emulsioncomprising at least one aqueous phase and at least one oil-phase. Thistopical emulsion may be of the oil-in-water type. More particularly,this topical emulsion may consist of a fluid emulsion, such as a milk ora fluid gel. The oil phase of the topical emulsion may consist of amixture of one or more oils.

A topical composition according to the invention may be intended for acosmetic use or may be used in order to prepare a medicinal productintended for the treatment of skin diseases and mucosal diseases. In thelatter case, the topical composition then contains an active principlewhich may consist, for example, of an anti-inflammatory agent, a musclerelaxant, an antifungal agent or an antibacterial agent.

When the topical composition is used as a cosmetic composition intendedto be applied to the skin or the mucosae, it may or may not contain anactive principle, for example a moisturizing agent, a tanning agent, asunscreen, an anti-wrinkle agent, an agent intended for slimming, ananti-free-radical agent, an antiacne agent or an antifungal agent.

A topical composition according to the invention usually containsbetween 0.1 and 10% by weight of the thickener defined above. The pH ofthe topical composition is preferably above or equal to 5, and is, morepreferably between 6 and 12.

The topical composition may also contain compounds conventionallyincluded in compositions of this type, for example fragrances,preserving agents, dyes, emollients or surfactants.

A topical composition according to the invention may be prepared in amanner known to those skilled in the art, for example according to theprocess described in patent application EP-A-0,503,853.

According to another aspect, the invention relates to a novel thickenercomprising a water-in-oil emulsion and a copolymer, the copolymer havingmoieties derived (i) from a monounsaturated monocarboxylic acidcontaining from three to five carbon atoms, the monocarboxylic acidbeing in free form or in the-form of an inorganic salt, and (ii) from amonoacrylamide monomer,

the copolymer being in solution in the aqueous phase constituting thesaid emulsion,

the oil phase of the said emulsion consisting of a mixture between atleast one volatile oil and at least one non-volatile oil.

The various quantitative and qualitative characteristics of thisthickener are as described above.

According to a most particularly advantageous aspect of the invention,the said oil phase constituting the thickener in accordance with theinvention comprises a mixture between, on the one hand, an isoparaffinoil and, on the other hand, a liquid paraffin or isostearyl isostearate.

According to yet another aspect, the invention relates to the use of thenovel thickener in accordance with the invention mentioned above, forthickening and emulsifying a topical composition comprising at least oneaqueous phase.

The examples which follow are intended to illustrate the presentinvention.

EXAMPLE 1

A thickener in accordance with the present invention is prepared usingthe process described in patent application EP-A-0,186,361, so as toobtain a water-in-oil emulsion having the following composition (% byweight):

copolymer comprising: moieties derived from a monoacrylamide  7.5%monomer moieties derived from a sodium  9.5% acrylate monomerN,N-methylenebis (acrylamide)  0.2  meq/mol of monomer isoparaffin 15% liquid paraffin 15%  montanox 85 SPI⁽¹⁾  4%  laureth 7⁽²⁾  2%  water qs100% ⁽¹⁾polysorbate marketed by the company Seppic ⁽²⁾lauryl alcoholethoxylated with 7 units of ethylene oxide.

Copolymerization of the monomers is performed according to the reverseemulsion polymerization process, in a water-in-oil emulsion whose oilphase consists of isoparaffin. The liquid paraffin is introduced intothe mixture obtained after copolymerization.

EXAMPLE 2

Another thickener in accordance with the present invention is preparedaccording to the process described in patent application EP-A-0,186,361.To this end, in a first stage, a water-in-oil emulsion is prepared,comprising:

copolymer comprising moieties derived: from a monoacrylamide monomer8.3% from a sodium acrylate mononer 10.8%  N,N-methylenebis(acrylamide)0.2  meq/mol of monomer isoparaffin 15%  montane⁽³⁾ 1.2% oleamide DEA⁽⁴⁾2.4% water 38.3%  and in the second step, a mizture comprising 15% byweight of isostearyl isostearate and 9% by weight of montanox 60⁽⁵⁾(relative to the total weight of the final emulsion obtained) is thenintroduced into this emulsion. ⁽³⁾sorbitan oleate marketed by thecompany Seppic ⁽⁴⁾mixture based on oleic acid diethanolamide (INCInomenclature) ⁽⁵⁾sorbitan stearate ethoxylated with 20 units of ethyleneoxide (or Polysorbate 60), marketed by the company Seppic.

EXAMPLE 3

The process is performed as in Example 1, using 12% by weight ofmonoacrylamide monomer and 6% by weight of a sodium acrylate monomer, soas to obtain another thickener in accordance with the invention.

EXAMPLE 4

An oil-in-water emulsion is prepared by mixing the following compounds(% by weight):

thickener  x % primol 352⁽⁶⁾ 10% water qs 100% ⁽⁶⁾liquid paraffinmarketed by the company Esso.

The thickener used is either that of Example 1, in accordance with theinvention, or a thickener comprising the copolymer as prepared inExample 1 of patent application EP-A-0,503,853, by way of comparison.The comparative thickener is prepared according to the process ofExample 1 of EP-A-0,503,853, after adaptation for the purpose ofobtaining a composition which differs from that of the thickener inaccordance with the invention only in the actual nature of thecopolymer. This adaptation consists in diluting the thickener accordingto Example 1 of EP-A-0,503,853 with water and suitable oils, in orderfor the concentration of copolymers to be identical to that of thecopolymer of the thickener according to Example 1 above.

The oil phase, the aqueous phase and the various surfactants are thusquantitatively and qualitatively identical for each thickener tested.Furthermore, each of these thickeners contains an identicalconcentration of copolymers.

Measurement is made of the viscosity of various oil-in-water emulsionsas defined above, comprising variable concentrations of thickener inaccordance with the invention or of thickener according to the priorart.

The viscosity measured is expressed in Pa s. It is measured using aBrookfield LV4 viscometer rotating at 6 revolutions/minute. The resultsobtained are presented in the FIGURE. The viscosity is on the y-axis.The concentration of thickener (% by weight) is on the x-axis.

It is considered that below a viscosity of about 25 Pa s, theoil-in-water, emulsion is a milk (fluid emulsion) and that above thisvalue, it is in the form of a cream.

It may be observed that as soon as the concentration of thickeneraccording to the prior art exceeds 2% by weight, the said emulsion is inthe form of a cream. In contrast, the thickener in accordance with theinvention may be used at concentrations of greater than 3% by weightwithout the emulsion being in the form of a cream.

The FIGURE also shows that the curve in accordance with the inventionhas a much lower slope than that obtained with a thickener according tothe prior art. It emerges therefrom that slight variations inconcentration of the thickener according to the invention do notsignificantly modify the viscosity of the composition prepared. Incontrast, slight variations in the concentration of the thickeneraccording to the prior art lead immediately to considerablemodifications in the viscosity of the composition prepared.

The thickener in accordance with the invention thus makes it possible toobtain fluid emulsions, such as a milk, in a reproducible manner on anindustrial scale, this not being the case for the thickener of the priorart.

EXAMPLE 5

The skin tolerance of the thickeners of Examples 1 and 3 was tested. Thenon-volatile oil constituting the thickener, introduced aftercopolymerization, is of variable nature.

The weight ratios between the isoparaffin and the non-volatile oil,which constitute the thickener, were also varied.

The tests were performed using an aqueous solution comprising (% byweight):

thickener  5.0% water 95% 

The results obtained are featured in the table below.

Tolerance (%) as a Molecular function of the iso- weightparaffin/non-volatile Non-volatile of the non- weight ratio Test oilvolatile oil 47/53 67/33 100/0 1 primol 352⁽¹⁾ 470 100 60 15 2isostearyl 536 85 isostearate ⁽¹⁾Thickened liquid paraffin marketed bythe company Esso.

The skin tolerance was determined according to the so-calledepicutaneous test under occlusion (patch test) in man.

Small aluminium cups 8 mm in diameter and 20 microlitres in capacitywere used, each cup allowing a surface area of 50 mm² to be covered.They are mounted in pairs on an adhesive tape.

The aqueous solution impregnates discs of blotting paper which arespecially adapted to the cup/adhesive system. The system is applied tothe skin (left sub-capular region) of the individuals. Fourteenvolunteers, with an average age of 29, served as test individuals.

By way of reference, a 2% solution of sodium lauryl sulphate, as well asdistilled water serving as a control, were also applied in the samemanner to each individual but to a different area of skin.

24 hours after the application, the cups are removed from the areas-onwhich they have been applied.

The results are read 30 minutes and then 24 hours after installation.

In order to examine whether or not the products applied are tolerated,the appearance of the following phenomena was considered:

erythema,

oedema,

blisters,

dry skin,

rough skin,

reflex excitability of the skin.

The percentage of skin tolerance expressed in the above tablecorresponds to the number of individuals who exhibited none of thephenomena mentioned above, relative to the total number of individuals,after the reading taken at 24 hours.

EXAMPLE 6

In order to assess the stability of the viscosity imparted by thethickener according to the invention, a dispersion of the thickeneraccording to Example 1 in water was prepared, such that the viscosityobtained is 80 Pa s (Brookfield LVT4, 6 revolutions/minute).

By way of comparison, an aqueous dispersion thickened to 80 Pa s wasprepared using the comparative thickener defined in Example 3.

0.1% by weight of a salt was then introduced into each of the thickenedaqueous dispersions. This salt is either sodium chloride or magnesiumchloride (MgCl₂).

The aqueous dispersion thickened with the thickener in accordance withthe invention, in which sodium chloride is added, thus has its viscosityreduced to 57 Pa s with NaCl and to 61 Pa s with MgCl₂. The aqueousdispersion thickened with the comparative thickener has its viscosityfall to 13 Pa s with sodium chloride and to 16 Pa s with magnesiumchloride.

EXAMPLE 7

A make-up-removing milk is prepared by mixing (% by weight):

montanov 94⁽⁷⁾: 3.0% primol 352: 8.0% HAD⁽⁸⁾: 2.0% thickener of Example1: 0.8% water qs 100% ⁽⁷⁾nonionic surfactant marketed by the companySeppic ⁽⁸⁾sweet almond oil marketed by the company Bertin.

A preserving agent and a fragrance were added to this mixture.

The viscosity of this composition is 15 Pa s and its pH is 7 (afteradjustment); it is stable for 1 month at 50° C. and for 3 months at 40°C.

EXAMPLE 8

A body milk is prepared by cold-mixing (% by weight):

lanol 99⁽⁹⁾ 10.0% thickener of Example 1:  1.4% micropearl M100⁽¹⁰⁾: 0.2% water qs 100% ⁽⁹⁾isononyl isononanoate marketed by the companySeppic ⁽¹⁰⁾polymethyl methacrylate marketed by the company Seppic

A preserving agent and a fragrance are added to this mixture.

The viscosity of this composition is 12 Pa s and its pH is 6 (afteradjustment); it is stable for 2 weeks at 50° C. and for 3 months at 40°C.

EXAMPLE 9

A body milk is prepared by mixing (% by weight):

montanov 94: 3.5%  lanol 37T⁽¹¹⁾: 8.0%  benzophenone: 2.0%  dimethicone350 cPs: 0.05% solagum L⁽¹²⁾: 0.05% thickener of Example 1: 1.5%  waterqs 100% ⁽¹¹⁾glyceryl triheptanoate marketed by the company Seppic⁽¹²⁾carrageenan marketed by the company Seppic

A preserving agent and a fragrance are added to this mixture.

The viscosity of this composition is 18 Pa s and its pH is 6 (afteradjustment); it is stable for 1 month at 50° C. and for 3 months at 40°C.

EXAMPLE 10

An emulsion which is fluid at alkaline pH is prepared by cold-mixing (%by weight):

marcol 82⁽¹³⁾:  5.0% thickener of Example 1:  1.5% NaOH: 10%  water qs100% ⁽¹³⁾liquid paraffin marketed by the company Esso.

The viscosity of this composition is 10 Pa s and its pH is 12 (afteradjustment); it is stable for 2 weeks at 50° C. and for 3 months at 40°C.

EXAMPLE 11

A fluid foundation is prepared by mixing (% by weight):

simulsol 165⁽¹⁴⁾: 5.0% lanol 99: 5.0% lanol 84D⁽¹⁵⁾: 8.0% thickener ofExample 1: 1.2% inorganic fillers and pigments: 10.0%  water qs 100%⁽¹⁴⁾self-emulsifiable glyceryl stearate marketed by the company Seppic⁽¹⁵⁾dioctyl malate marketed by the company Seppic.

A preserving agent and a fragrance are added to this mixture.

The viscosity of this composition is 20 Pa s and its pH is 6 (afteradjustment); it is stable for 1 month at 50° C. and for 3 months at 40°C.

EXAMPLE 12

A sun milk is prepared by mixing (% by weight):

montanov 94: 3.5% lanol 37T 10.0%  parsol NOX⁽¹⁶⁾: 5.0% eusolex4360⁽¹⁷⁾: 2.0% thickener of Example 1: 1.8% water qs 100% ⁽¹⁶⁾sunscreenmarketed by the company Givaudan ⁽¹⁷⁾sunscreen marketed by the companyMerck.

A preserving agent and a fragrance are added to this mixture.

The viscosity of this composition is 18 Pa s and its pH is 7 (afteradjustment); it is stable for 1 month at 50° C. and for 3 months at 40°C.

EXAMPLE 13

A gel to be applied around the eyes is prepared by mixing (% by weight)

thickener of Example 1: 2.0% sodium pyrrolidonecarboxylate: 0.2%cyclomethicone⁽¹⁸⁾: 2.0% water qs 100% ⁽¹⁸⁾Dow Corning 245 fluidmarketed by the company Dow Corning.

A preserving agent and a fragrance are added to this mixture.

The viscosity of this composition is 15 Pa s and its pH is 6 (afteradjustment); it is stable for 2 weeks at 50° C. and for 3 months at 40°C.

What is claimed is:
 1. In a thickener for a composition for topicalapplication, consisting essentially of a water-in-oil reverse emulsionof a copolymer having moieties derived (I) from a monounsaturatedmonocarboxylic acid monomer containing 3 to 5 carbon atoms, the monocarboxylic acid either being in free form or in the form of an inorganicsalt, and (II) from monoacrylamide; the improvement wherein thecopolymer also contains a polyfunctional monomer, the copolymer is insolution in the aqueous phase constituting said emulsion, the oil phaseof said emulsion consists essentially of a mixture of at least onevolatile oil and at least one non-volatile oil and the thickener alsocomprises at least one non-ionic surfactant selected from the groupconsisting of alkylpolyglycosides, and wherein the volatile oil is avolatile isoparaffin, and the non-volatile oil is a paraffin orisostearyl isostearate.